1. Field of the Invention
The present invention relates to a method of joining sheet members together and a sheet jointed body, and more particularly to a method of joining sheet members together, in which band-shaped sheet members are jointed together, and a sheet joined body formed by joining band-shaped sheet members together.
2. Description of the Related Art
Hitherto, when band-shaped sheet members are to be continuously fed to a processing machine to be processed, a leading end of a newly fed sheet member is joined to a tail end of a preceding sheet member so as to successively feed the newly fed sheet member subsequent to the preceding sheet member to the processing machine.
Hitherto, as a joining method of this kind, as shown in FIG. 5A, a tail end of a preceding sheet member 101 is held abutting against a leading end of a newly fed sheet member 102, and adhesive tapes 103, 103 are attached to both the sheet members onto both the upper and lower surfaces, covering the abutted portion, thereby joining the two sheet members 101, 102 together.
In a case where the sheet members 101, 102 are joined together by the above method, a stepped portion is caused at a joined portion due to the adhesive tapes 103. For example, a coated film coated in a subsequent coating step may cause liquid stagnation due to the stepped portion, or a conveying roll or a nip roll may contact edges of the adhesive tapes 103 and hence may be contaminated or damaged. Another problem lies in that an adhesive agent of the adhesive tapes 103 may be fluidized due to the heat such as in a drying step, and hence the adhesive strength may be deteriorated.
As shown in FIG. 5B, there is proposed another method of joining the sheet members 101, 102, in which a newly fed sheet member 102 is overlapped onto a preceding sheet member 101, and they are joined together via an adhesive tape 103 previously disposed at a leading end portion of the newly fed sheet member 102, and then a side rearward to the preceding sheet member 101 is cut.
However, when the above method is employed, a stepped portion of the joined portion is further enlarged and a tail extension 104 is formed at the tail end of the preceding sheet member 101, which causes a problem in that the tail extension 104 flutters when in conveying the sheet members, and there is a problem in that generation of refuses is triggered, in addition to the aforesaid problem due to the stepped portion.